摘要
Abstract
Titanium ion-sieve is prepared by acidification delithiation process,which has the advantages of large adsorption capacity,high selectivity and good cycle stability,but its performance and effect in practical application need to be verified.In this paper,the effects of temperature,pH,lithium ion concentration,feed flow rate and adsorption time on the adsorption performance of titanium ion sieve were systematically investigated by single factor test.The microstructure,crystal structure and pore characteristics of the materials are analyzed by scanning electron microscopy(SEM),X-ray diffraction(XRD)and brunauer-emmett-teller analyzer(BET).The results show that the adsorption capacity is positively correlated with various factors within the test range.The optimum process parameters obtained by single factor test are as follows:feed temperature 20℃,feed flow rate 12 BV/h,adsorption time 3 h.Based on the optimal process parameters,the dynamic adsorption verification test of raw brine from a salt lake in Tibet is carried out.The results show that the adsorption capacity of the ion sieve is 12.1 mg/g,the lithium distribution coefficient is 112.68 mL/g,and the lithium concentration coefficient is 38.46 L/mg under the complex brine system,showing good adsorption selectivity and good engineering applicability.In the process of desorption,the desorption of impurity ions is mainly concentrated in the early stage of desorption.Based on this,a pre-desorption process is pro-posed,which can effectively improve the purity of lithium-rich solution.The research results can provide a theoretical basis for the optimization of lithium extraction process of titanium ion-sieve.关键词
钛系离子筛/吸附法/吸附容量/离子选择性/盐湖提锂/单因素试验/解析工艺Key words
titanium ion-sieve/adsorption method/adsorption capacity/ion selectivity/lithium extraction from salt lake/single factor test/analysis process分类
化学化工
